1. Technical Field
The present invention relates to an endoscope apparatus, an endoscope system and a method for controlling an endoscope apparatus.
2. Description of Related Art
As an apparatus for observing the inside of a body cavity, the inside of a tube included in a structure, and the like, there is widely used an endoscope apparatus. The endoscope apparatus includes an endoscope insertion portion to be inserted into a sample, and a main body operation portion disposed continuously with the base end of the endoscope insertion portion, while on the leading end side of the endoscope insertion portion, there is formed a curving portion which can be curved through the pulling operation of an operation wire inserted through the endoscope insertion portion. The operation wire can be pulled by operating an angle knob disposed on the main body operation portion in a desired direction to thereby curve the curving portion in a desired direction. As an example of such endoscope apparatus, there is disclosed in JP-A-2009-90087 an endoscope apparatus with a power assisting function structured such that, in order to reduce the operation force of the angle knob for curving the curing portion, an operation assisting force for assisting the pulling of the operation wire is generated using an assisting drive motor to thereby apply the operation assisting force to a wire pulling member. According to the disclosed endoscope apparatus, in addition to the operation force of the angle knob to be applied by an operator who operates the endoscope apparatus, the operation assisting force generated by the drive motor provided within the main body operation portion is applied to the angle knob. Therefore, while reducing the operation force, the curving portion can be curved by a desired amount.
In the case of the above-mentioned operation assisting force, while the size of the operation assisting force is set according to the operation of the angle knob, the operation assisting force is applied as the operation assisting force of the operator. However, the desired characteristics of the operation force to be applied to the curving operation portion vary depending on the taste of the operator, the manipulation contents of diagnose and care using the endoscope apparatus, or on the individual difference between endoscopes such as the bending rigidity of the respective endoscope insertion portions thereof. Therefore, it is expected that the curving characteristic itself expressing the relationship between the operation force to be applied to the angle knob and the curving angle of the curving portion can be changed, whereby the feeling of the operator in using the endoscope can be made more natural.